Perhaps you should try some spelling variations:
sach thu » sach thue, sach thieu, sach tham
cam thuc » am thuc, nam thuc, cam thu
hanh di » hanh vi, hanh de, hang di
cua tre » cuu tre, cua triet, dua tren
xang xa » lang xa, mang xa, ang xa
hieu va » lieu va, hieu qua
sach ty » sach y, sach tu, xach tay
thuc va » thuc vat, thuc dan, thuc day
va hanh » van hanh, va thanh, va danh
va cam » va cham, va cac, va cao
cua te » cua tu

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: te ((sach ty) OR (sach thu)) xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (cua te))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: te ((sach ty) OR (sach thu)) xang xa hoi. hieu va cam thuc va hanh di ((cua tre) OR (cua te)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "te ((sach ty) OR (sach thu)) xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (cua te))".
• Adding a wildcard symbol may retrieve word variants: te ((sach ty) OR (sach thu)) xang xa hoi. hieu va cam thuc va hanh di ((cua tre) or (cua te))*.